Hello again RO. Been an eventful and long time since I've been back here. I finally opened my studio, Vibrations Recordings in September of last year with so much incredible support from so many great folks here for the last 17 years or more!.
Recently Kmetal, who has become an incredible mentor and friend, and I, have been running REW programs to fine tune the CR. Room design and treatments along with speaker placement experiments have provided a relatively "flat" room response curve.The last thing needed is to tame a 60Hz bump. and the only viable options I've come across are commercial units costing up to 15k (eek!) or the use of a bass array with DSP to possibly utilize phase offsets to tame the beast.
Through my research the resources I found only seem to address using a bass array in a square room. My CR is a corner design. The rest of the response curve seems pretty good and translation so far of projects seems adequate. Perhaps I'm just naturally compensating for the 60 cycle bump?
Either way The REW results are consistent and I want to do all I can to control it within reason and cost. I'm wondering if anyone here has had any experience with the bass array solutions or have any other suggestions to offer?
I apologize for being so out of touch and hope to follow up with pictures of the digs so wonderfully saved by Rod G. after my humble attempts to do it all myself!
Comments
Hey, nice seeing a post from…
Hey, nice seeing a post from you! Great name for your studio too. I'd love to see pics sometime and of course any mixes. I love hearing what our member are doing!
Sorry I can't help on that bump and wow, 15k, yikes!
Glad you and Kyle are in touch, say hi to him from me. Looking forward to any suggestions others may have.
Hi Vibrations, and good to…
Hi Vibrations, and good to see you again!
Your studio sounds really good, and some pics would be great.
Regarding the 60Hz rise in your response curve, what type of monitors are you using? Are they powered or do you have a separate full-range power amp and then crossover networks for splitting high/mid/bass at the speakers?
If you have powered monitors using standard line-level inputs, it's not that difficult to make a passive filter to fit inline with the inputs to deal with a single-frequency anomaly. You may lose a dB or so on level, but that can usually be made up by adjustment of the gain trims on the rear of the monitors. Can you show an example frequency response plot to illustrate the height and width (to get the Q) of the resonance?
Bos
Hello Chris and Bos. Thanks…
Hello Chris and Bos. Thanks so much for responding! My web site is vibrationsrecordings.com. Also on FB.
Life doesn't seem to want to slow down much lately though I intend to follow up with pix and sound files. I'll also do my best to post some REW shots.
For now, to provide more details:
1. Speakers are passive: PMC IB1's, Internal crossovers with potential isolation of feeds to all three speakers on each. All connected right now with one amp ea. speaker.
2. Driven by 2 Hypex digital amps Purely amps with no other functions.
3. Orion 32+ interface. No equing possible within it that I'm aware of
4. Studio one 7 DAW. It would be challenging to preset equing mains 2bus for each project, even though my templates could be preset. Seems like it might be a wonky way to approach this?
Thansk guys and I'll be back with pix and sounds soon.
Later!
some studio grand opening pictures
more pix
That looks really good!…
That looks really good!
Congratulations!
PS your graphs did not show. Try using the "Image" button at the top of the Comment box to import an image into the RO domain.
Filter for mains
@ Bos. You wrote " it's not that difficult to make a passive filter to fit inline with the inputs to deal with a single-frequency anomaly."
Since I don't have powered speakers could something like this work in-line between my Dangerous ST speaker outputs and the Hypex amps to the passive mains?
If so I could build a similar configuration for my alternate passive speakers as well.
screen shot
I could only take a screen shot of the graph and save it to pictures or documents but don't know how to save it as a jpeg etc.
Any ideas?
rew graph
Yes, if you can install them…
Yes, if you can install them in the path between your Dangerous ST and the power amps for the respective speakers.
The main advantage of line-level active filtering is that you can implement much more accurate and predictable filter responses, as there is no direct interaction with the loudspeaker voice coils.. A minor disadvantage is that you need a mains connection for powering the filters, but the power consumption would be only a few Watts.
Have you established that the acoustic response curves for the studio are the same for measuring with the main monitors and the alternate speakers?
Regarding posting pictures, I make use of the many free on-line conversion services that will take (say) a .pdf and convert it to a .jpg. You sometimes have to try a few to get one that Paint will squash to an acceptable size for posting here on RO.
Great looking setup!
Great looking setup!
I could only take a screen…
Are you trying to upload a pdf?
line filters
Excellent!!!! The filters are nothing I am familiar with but feel confident that with a wiring diagram and components list I could likely build them myself??
Are such filters available premade? The power consumption wouldn't be an issue for me. I've begun researching Drive Rack options yet that seems like it may not be a reasonable option and possibly kinda overkill.
I have not had the chance to test my second set of speakers yet and that's a very good question.
I'll look into reformatting more pictures I have to post. I'm also hoping to post some audio files soon as well!
Looking forward to you responses and by the way, thanks so much for the compliments on the studio. Life's dream for sure. Only took 17 years from inseption to get here but well worth it!!
Cheers and thanks again!
What I would recommend is to…
What I would recommend is to borrow or rent a good-quality stereo analogue graphic equaliser. Many years ago I evaluated several different types for use in "ringing out" venues and auditoria in my live sound work. I settled on Audient ASP231 units as being easily the best of the ones I tested for sound quality, phase coherence and setting accuracy. I have 4 of them in my hire stock, but I never got to the bottom of why graphic EQs get such a battering when out on hire.
Largely for phase reasons, I would normally be very hesitant in suggesting the use of graphic equalisers in studio operations. However, you are effectively doing live sound work when using frequency sweeps to measure your studio acoustics, so they are permitted for this.
The ASP231 has 50Hz and 63Hz filters in the relevant region, and it has balanced I/O on XLRs. You should be able to set it up feeding your main monitor power amp and then run your sweeps experimenting with different graphic settings. Make a note of the amount of adjustment needed to flatten any peaks and troughs that are more than about 1dB off flat. This gives the starting values for a fixed band-pass or a notch filter for a more permanent device to incorporate into your system, albeit with a bypass switch.
Great idea Bos
A quick search for ASP231 provided no results. Would another unit suffice like perhaps the DBX stuff? I do have a DBX 1231 racked for my live room JBL's.
I'll keep looking. I have no "local" rental options so rental and shipping might get so costly it would be best for me to purchase and resell when done with it.
Thanks Bos
The DBX1231 is not one that…
The DBX1231 is not one that I tested, but its spec looks fine for this sort of test. It has the ISO list of centre-frequencies and has balanced I/O, so it should be just as usable as the Audient. Who'd have thought you had the very box sitting in one of your racks!
Whoot! A leftover from my…
Whoot! A leftover from my past sound reinforcement days!
I'll let ya know what I find once I get a chance. Thanks so much Bos!